Machines for cutting mat board, such as is used in picture framing and the like, are well known in the art and are in widespread use. A particularly desirable machine of this kind is commercially available from The Fletcher-Terry Company, of Farmington, Conn., and is described in copending application for U.S. Pat. Ser. No. 07/013,578, entitled "Mat Bevel Cutting Machine", filed on Feb. 11, 1987 in the names of Kozyrski et al, and of common assignment herewith.
Mat board cutting machines typically consist of a base and a pivotably attached handled assembly, which in turn slideably mounts a cutting head and carries a clamping bar. The machine is used simply by placing the piece of mat board to be cut upon the surface of the base, and lowering the handle assembly upon it; this serves both to position the head for cutting, and also to hold the workpiece in place under the clamping bar.
It is conventional for such a machine to have straight-edge features for positioning the workpiece relative to the cutting axis, and at minimum a guide edge will normally be provided which is parallel to the travel path of the cutting head. Devices are however also available for positioning the mat in other orientations.
Although in most instances mats cut for picture framing will be rectangular, and formed with parallel-sided rectangular sight openings, in many cases it will be desirable to cut the mat with a non-rectangular exterior configuration and/or with a non-rectangular polygonal sight opening, which may or may not be oriented to provide internal and external edges that are parallel to one another. To perform the cutting operations necessary to produce such shapes, with optimal accuracy and facility, the machine will most advantageously employ a device that is capable of engaging a corner of the mat, and of positioning it in each of a range of angular orientations relative to a reference line (i.e., the travel path of the cutting head).
So-called "multi-angle" mat guides, providing such capabilities, have heretofore been offered commercially. They are often found however to afford less accuracy and convenience of use than may be desired, and to be of unduly complex design and construction.
Accordingly, it is the broad object of the present invention to provide a novel angle mat guide device for engaging an edge of a workpiece to effect positioning thereof, which device will afford a high degree of accuracy and convenience in use, and is of relatively uncomplicated and inexpensive design and construction.
It is a more specific object of the invention to provide such a device by which both adjacent edges at a corner of the workpiece can be engaged simultaneously, to thereby provide the utmost accuracy, reproducibility and facility in carrying out the cutting operations.
Another specific object is to provide a novel device having the foregoing features and advantages, which is adapted for mounting upon a guide member, particularly one having a portion of generally triangular configuration, and for facile securement at each of a multiplicity of positions along the length thereof.